T1024 NOR Flash CFG_RCW_SRC Setting

We have a custom board that has T1024 and a 128 MB x16 NOR Flash. In the Reference Manual, page 1084, it says that address shift value is 5. However, in the cfg_rcw_src field there is no option such 5, only 4, 7, 10 shift values are available. What value should I select for the cfg_rcw_src field?

In the reference design IFC_A29 and IFC_30 pins are used as address bits, but we use these pins as IFC_RB2 and IFC_RB3, because we have devices more than two on the IFC bus. So, we followed the reference manual while designing our board. Is there a way of booting CPU from NOR flash using the connections on the Reference Manual, Figure 23-9.